Apparatus for coiling cold rolled strips



March 27, 1956 A. w. SlLFVERLlN ET AL 2,739,763

APPARATUS FOR COILING COLD ROLLED STRIPS Filed Dec. 25, 1952 INVENTORS a4: wfi'mw e-M M ATTORNEYS United States Patent APPARATUS FGR COILING COLD ROLLED STRIPS Ade William Silfverlin and Gustaf Harald Sjiiherg, Sandvilien, Sweden, assignors to Sandvikens Jernverks Aktiebolag, Sandviken, Sweden Application December 23, 1952, Serial No. 327,507 Claims priority, application Sweden December 28, 1951 3 Claims. (Cl. 242-78) This invention relates to apparatus for coiling cold rolled strips or the like, and more particularly apparatus for so coiling the material that the wound coils do not tend to expand or loosen when removed from the apparatus.

The coiling of cold rolled strip metal on driven drums or so-called drawing coilers has been attended with difliculties since the wound coil tends to unwind and must be bound in some manner to retain its coil form before it is removed from the coiler. In the case of the thicker and harder strip material, the last turn or turns must be held in place or compressed upon the adjacent inner turns by some form of brake or clamp mechanism while a retaining strap is riveted or welded around the coil. The mechanism has been complex and time consuming, it required the services of a number of workmen, and there was an element of danger in working around the heavily stressed wound coil. In addition to these disadvantages, the last turns could expand to some extent if the retaining strap was not tightly applied to the clamped coil, and this slippage of the outer turns frequently resulted in a scratching of the surface of the strip material.

Objects of the invention are to provide apparatus for and methods of coiling cold rolled strip material and the like in such manner that the outer turns of the coils are tightly engaged with the inner turns and prevent an inadvertent unwinding of the coil. An object is to provide apparatus of drawing coiler type for coiling cold rolled strip material, the apparatus including a bending device consisting of at least two and preferably at least three idler rolls which may be brought into operation at an arbitrary stage in a coil forming operation to bend the final turns of the coil to such curvature that it does not unwind to any appreciable extent. An object is to provide a method of winding a coil of cold rolled strip material on a drawing coiler, the method being characterized by a prebending of the last turns of the coil to a smaller radius of curvature than they will have when incorporated in the coil.

These and other objects and the advantages of the invention will be apparent from the following specification when taken with the accompanying drawing in which:

Fig. 1 is a somewhat schematic side elevation of coil winding apparatus embodying the invention as seen at the start of a coil winding operation; and

Fig. 2 is a similar view of the apparatus with the bend' ing device in operation at or near the end of a coil wind' ing operation.

As shown in Fig. l, the end 8 of the strip material S delivered from the rolls 9 and 10 is introduced into the slot 11 of the drum or coiler 12 which is driven counterclockwise, as indicated by the arrow, at such speed as to maintain the strip material under substantial tension. The coiler may be driven by any convenient power source, not shown, which may be a separate motor or a line shaft which also operates other equipment of the rolling mill.

In accordance with the invention, a bending device is effectively positioned between the rolls 9, 1t) and the driven coiler 12, and is so constructed that it may be adjusted between an operative and an inoperative condition.

7 2,739,763 Patented Mar. 27, 1956 ice As illustrated, the bending device comprises idler rolls 13 and 14 at one side of the strip S and a third idler roll 15 at the opposite side of the strip. The idler roll 15 is supported in one end of an angular arm 16 and, in the inoperative condition of the bending device as shown in Fig. 1, the roll 15 is between the coiler 12 and the rolls 9, 10 and is beneath and spaced from the lower surface of the strip S. The arm 16 is pivoted on a stud or shaft 16a below the coiler 12 and at the side thereof remote from the rolls 9, 10, and it may be rocked countercloclo wise by a pressure cylinder 17 to engage the roll 15 with the strip S and move the latter into contact with the idler rolls 13 and 14. These rolls are journalled in a frame 18 which may rock upon a supporting stud 19 in accord ance with the extent to which the roll 15 is moved towards the idler rolls 13 and 14. The frame 18 and idler rolls 13, 14 are located at a substantial distance to one side of the minimum length path of the strip S between the rolls 9, 10 and the coiler 12, and preferably at a somewhat greater distance from the rolls 9, 10 than the coiler, whereby the strip is reversely bent upon itself when the roll 15 is moved into operative position.

The roll 15 is moved into inoperative position, as shown in Fig. 1, at the start of a rolling operation to facilitate the insertion of the strip end 8 in the slot 11 of the driven coiler 12. At least a few turns of the strip S are wound upon the coiler 12 to anchor the end 8 securely in the slot 11 before the arm 16 is rocked to bring the bending device into operation, and only the last turn or last few turns of the coil need be prebent in those cases in which the subsequent use of the coiled strip will not be detrimentally affected by a tendency of the coil to unwind after the outer turns are drawn off. The degree of bending is determined by spacing of the roll 15 with respect to the rolls 13 and 14. When the roll 15 is forced as tightly as possible towards the other rolls, the strip S is bent to substantially the curvature of the roll 15. The further the roll 15 is spaced from the rolls 13, 14, the greater the radius of curvature of the bent strip will be. To obtain the desired self-locking of the coil against unwinding, the strip must of course be prebent to a smaller radius of curvature than that which the strip will have when wound upon the coil.

Contrary to what might have been expected, the heavy tension applied to the strip S by the drawing coiler 12 does not eliminate the prebending of the strip by the idler bending rolls. As compared with the prior practice of employing a bending device with driven rolls for delivering the bent strip to a non-driven coiler, the invention has the advantage of a much higher rate of production. For example, in one cold rolling mill the maximum rate of rolling and coiling of the strip material was 18 meters per minute with the prior equipment of driven bender rolls and an undriven coiler, and the rate was increased to meters per minute through use of the drawing coiler and idler bending roll-s of this invention.

The term strip is employed in a generic sense in the above specification and in the following claims, and it is to be understood that it does not imply any limitation to the cross-section of the material being rolled and coiled. The term includes, among others, bands of rectangular cross-section and rods or wires of circular cross-section.

It is to be understood that the invention is not limited to the particular embodiment herein illustrated and described, and that various modifications thereof which may occur to those familiar with the art fall within the spirit and scope of the following claims. For example, in place of the illustrated three bending rolls it is possible and practical to employ more or less than three idler bending rolls.

We claim:

1. Apparatus for coiling cold rolled strip material passed through and delivered by a pair of rolling rolls comprising a drawing coiler having means for securing the leading end f sai strip ma rial, eans for ri ng said. coiler at a speed to maintain said strip material under substantial tension and simultaneously wind the same upon said c-oiler, and means interposed between said rolling rolls and coiler for bending said strip material as it is being drawn by said coiler, said bending means comprising relatively stationary idler roll means located at one side of and spaced from said strip material passing in a minimum path between said rolling rolls and said driving coiler, relatively movable idler roll means located at the opposite side of said strip material and having an active and a nonactive position, said movable idler roll means in said nonactive position being spaced from said strip material passing in its minimum path between said rolling rolls and said driving coiler, said movable idler roll means in said active position contacting said stationary roll means, and means for moving said movable idler roll means in the direction of said stationary roll means to said active position and thereby displace said strip material out of its initial minimum path between said coiler and rolling rolls and cause said strip material to be pressed between said stationary and movable idler roll means and thereby bent prior to reaching said coiler.

2. Apparatus as defined in claim 1 for coiling cold rolled strip, material wherein said relatively stationary idler roll means is comprised of a pair of idler rolls journalled in a frame, and means for supporting said frame for rocking movement in response to pressure exerted thereon by movement of said movable idler roll means.

3. Apparatus as defined in claim 1 for coiling cold rolled strip material wherein said relatively stationary idler roll means is comprised of a pair of idler rolls journalled in a frame, means for supporting said frame for rocking movement in response to pressure exerted thereon by movement of said movable idler roll means, and wherein said movable roll means is supported by a pivotally mounted arm for movement towards and away from said pair of idler rolls.

References Cited in the file of this patent UNITED STATES PATENTS 1,230,944 Sundh June 26 1917 1,258,091 Clark Mar. 5, 1918 1,871,665 Dallas Aug. 16, 1932 2,179,011 Hudson Nov. 7, 1939 2,265,246 Ott Dec. 9, 1941 

